9 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Keston K170 MK2
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Your boiler is failing to light the burner, meaning it cannot provide you with any heating or hot water until the ignition system is professionally serviced.
Your boiler is failing to light the flame properly because it cannot communicate with the internal safety controls.
Your boiler is failing to light the flame because there is a loose or damaged connection in the internal wire that creates the ignition spark.
Your boiler is failing to light the gas burner correctly to provide heating and hot water.
Your boiler has failed to ignite or stay lit correctly, meaning it will not be able to provide heating or hot water until it is reset or repaired.
Your boiler has detected an issue with the gas flow or the internal component that delivers fuel to the burner, meaning it cannot ignite safely.
Your boiler has detected an incorrect settings or a hardware issue specifically related to how it processes liquid petroleum gas, meaning it cannot heat your home safely.
Your boiler has detected an incorrect internal air-to-gas ratio, which prevents it from firing up safely.
Your boiler has detected an issue with the air supply adjustment required for liquid petroleum gas (LPG) operation, preventing it from heating safely.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes